From e8d177d88f89db216362284533d6e7ed27f9382a Mon Sep 17 00:00:00 2001
From: Harald Welte <laforge@osmocom.org>
Date: Fri, 11 Feb 2022 17:08:45 +0100
Subject: [PATCH] tlv: Convert CamelCase class name to snake_case in json

Our hand-written JSON so far is using snake_case identifiers,
while the JSON generated by the pySim.tlv classes use the class
names as keys, which LooksQuiteDifferent.

So let's auto-convert the CamelCase into something that reflects
our existing notion.

Change-Id: Id55929ef03dc48cb668e6ba7e99b6b291680a42f
---
 pySim/tlv.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/pySim/tlv.py b/pySim/tlv.py
index 71338ab0..dc8cc4fd 100644
--- a/pySim/tlv.py
+++ b/pySim/tlv.py
@@ -31,7 +31,11 @@ from pySim.exceptions import *
 
 import inspect
 import abc
+import re
 
+def camel_to_snake(name):
+    name = re.sub('(.)([A-Z][a-z]+)', r'\1_\2', name)
+    return re.sub('([a-z0-9])([A-Z])', r'\1_\2', name).lower()
 
 class TlvMeta(abc.ABCMeta):
     """Metaclass which we use to set some class variables at the time of defining a subclass.
@@ -148,7 +152,7 @@ class IE(Transcodable, metaclass=TlvMeta):
             v = [x.to_dict() for x in self.children]
         else:
             v = self.decoded
-        return {type(self).__name__: v}
+        return {camel_to_snake(type(self).__name__): v}
 
     def from_dict(self, decoded: dict):
         """Set the IE internal decoded representation to data from the argument.